121553443 has 4 divisors (see below), whose sum is σ = 132603768. Its totient is φ = 110503120.

The previous prime is 121553423. The next prime is 121553447. The reversal of 121553443 is 344355121.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 344355121 = 11 ⋅31305011.

It is a cyclic number.

It is not a de Polignac number, because 121553443 - 2²¹ = 119456291 is a prime.

It is not an unprimeable number, because it can be changed into a prime (121553447) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5525146 + ... + 5525167.

It is an arithmetic number, because the mean of its divisors is an integer number (33150942).

Almost surely, 2^121553443 is an apocalyptic number.

121553443 is a deficient number, since it is larger than the sum of its proper divisors (11050325).

121553443 is a wasteful number, since it uses less digits than its factorization.

121553443 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11050324.

The product of its digits is 7200, while the sum is 28.

The square root of 121553443 is about 11025.1277997128. The cubic root of 121553443 is about 495.3616959889.

The spelling of 121553443 in words is "one hundred twenty-one million, five hundred fifty-three thousand, four hundred forty-three".